Social networking is necessary today for professionals to advance their career. Business men and women have to expand their network to expand their job opportunities or client and customer base for their company.

To many, the first social network for professionals that comes to mind is LinkedIn. However, there are a couple places that could double your network or join you with the right market for your product or services.

LinkedIn.com

LinkedIn reported near the end of 2011 that it had over 135 million registered users from around the world and over 20 million unique visitors a month from the U.S. alone.

LinkedIn offers a variety of features for users to connect easily with people they may know or who they have previously worked with. There are groups and an Answers featured area to share with others and easily build new networks. A user can also get information out there about their online business activities via LinkedInís applications platform. Share your blog posts and tweets easily with your connections.

There are also paid membership levels allowing companies to post jobs. Users can easily submit resumes for consideration.

BranchOut

BranchOut is a Facebook application to network professionally across your Facebook contacts. Where LinkedIn connects you across the networks of past and present business associates and colleagues, BranchOut is doing the same across the networks of friends and family. It adds more functionality to Facebook to create a professional profile. Please note that your personal information and status updates are excluded from BranchOutís professional profiles to protect your privacy.

BranchOut is free but does offer enterprise products for job seekers and recruiters.

MeetUp.com

Contradictory to online social networking, MeetUp helps bring like-minded individuals together offline at the local level. A profile is interest driven where you find others with similar interests by following groups and networking together locally when notified by MeetUp. Businesses have an opportunity to offer membership perks to groups to advertise their service or product to interested members.

Even if you join MeetUp for personal reasons to expand your network to others with similar interests, you are engaging with others who may have connections for you to build on in the future professional.

There are many other professional networking sites online. To find one right for you, check out social networks that have groups relevant to your business. If there are no groups related to your niche, consider if the network would reach your target audience by reviewing the activity of members at the site. They may represent the correct business or customer demographic you want to reach.